Trouble with .bmp?

[SymbioticDesign]

On my Mac I am trying to open Bitmap (.bmp) files in Photo (2.04). Each time I try, I get a notice saying that a color profile was selected for me. I see nothing but a transparent 600x600px square, which is the size of my document (a seamless graphic/bumpmap tile created in FilterForge that works fine in other software). 

I can load it by going into the directory, previewing it, then selecting Edit > Copy, going back into Photo 2 and Pasting it in. If I chose the right file, it will have the same name it was supposed to and all, though I will have to turn snap on and line up the pasted content. That is quite a work around.

[firstdefence]

Any chance you can upload the the bitmap for us to look at?

 

 

[SymbioticDesign]

Sure, it's just a texture I created in FilterForge...

knurling_seamless_7.bmp

I hope it wound-up getting attached? 

As it is a bitmap, you won't see it in the message.I's only 1.4 mb

Edited March 26, 2023 by SymbioticDesign
1st: Can't find the attachment. 2nd: Whoops, tried it again. Found both. Edge hid the first download in some Edge data Downloads system folder. Strange. The next one downloaded well and I found it in the downloads folder.

[thomaso]

Works here in V1, both opened and placed. - Does it behave differently for you if you place it instead of opening it?

[lacerto]

Obsolete.

[firstdefence]

Any reason why you have chosen BMP to export to over PNG?

I can reproduce the transparency issue, I opened in Preview, exported to TIFF and it opens fine as a TIFF in Affinity Photo v2

knurling_seamless_7.tiff

From Filter Forge, I used File > Export and left the export settings to PNG, all the files open as expected.

[SymbioticDesign]

When I was saving these files way back when, I thought to myself, what file format will never go anywhere? I guessed wrong? Shows the impact that the internet has made. I wanted no compression and was skeptic of needing any for such small files. This was the result of not realizing how much quality I had lost when I absolutely had to use jpeg because no one was supporting lzh, or pict, or tiff. I wanted to be safe. Bitmap was pure, simple as that.

Even though I knew Photoshop would be around, I was already looking for an alternative, because even back then it was super expensive. Now it is a small fortune.

[firstdefence]

Did you launch FF directly, not as the plugin feature?

I think I've found the reason, I opened Filter Forge (FF) directly instead of via Affinity Photo, when I Saved the render as BMP it posted the popup you see below (fig 1.) the BMP option is automatically set to 32bit, changing the export option to 24bit allows the texture to render in Affinity. 

Fig 1.

This option isn't seen if FF is launched via Affinity Photo as a plugin and export is used although you can use File Save As... and you will then be able to set the bitmap to 24bit. 

24bit Knurl seamless as plugin.bmp

24bit Knurl seamless.bmp

[SymbioticDesign]

Huh. Yeah, back then I wanted everything to be 64 bit (computers, servers, etc..) and so I probably wanted to keep as much color information as possible. Not because of the texture, but because I had worked at a magazine and we found it stupid to throwaway color data. So that was simply set to be the default.

Like I said, I wasn't worried about compression (or file sizes). I was buying hard drives a lot, but not over that, just because I do not want to throwaway color data. Not ever.

Hey, good find! Thanks for clearing that up!

Congratulations, I would never have found that answer. You did what no one else could. 

Cool beans.

Edited March 26, 2023 by SymbioticDesign
Forgot thanks & congrats

[R C-R]

6 hours ago, firstdefence said:

the BMP option is automatically set to 32bit...

So there is a bug in the V2 Affinity apps (including the most recent betas) that prevents 32bit BMP files from opening correctly?

[firstdefence]

It looks like it, I wonder if if it's something to do with alpha because the diff between a 24bit and 32bit is the inclusion of alpha in the 32bit, hence the very transparent result. 

[NotMyFault]

You can solve the issue with one click: after opening the BMP in Photo, use channels panel, select "Background Alpha", and "fill".

[firstdefence]

@NotMyFault Why do you think the bmp behaves like this? would you consider it a bug?

[NotMyFault]

1 hour ago, firstdefence said:

@NotMyFault Why do you think the bmp behaves like this? would you consider it a bug?

Probably a bug, as other apps like apple preview show the file correctly. I remember similar incidents with V2 were alpha channel gets wrongly interpreted in different situations, e.g.

• copy / paste from v2 to v1 (i reported this, but mods could not reproduce). 
• Pasting from other apps like browser or 3d renderer
• some tiff files opened wrong
• some photo files exports to raster formats missing certain layers.

In the past there were many rounding errors, occasionally causing overflow/underflow. Still unsolved for histogram where 0 values get shown as 1 values.

but all said just guesswork based on older incidents with similar symptoms. 

[NotMyFault]

this might be relevant an explain a possible root cause as @SymbioticDesign mentioned the files are created a long time ago:

https://learn.microsoft.com/en-us/windows/win32/wic/bmp-format-overview

EnableV5Header32bppBGRA

Specifies whether to allow encoding data in the GUID_WICPixelFormat32bppBGRA pixel format. If this option is set to VARIANT_TRUE, the BMP will be written out with a BITMAPV5HEADER header.

The default value is VARIANT_FALSE.

If an encoder option is present in the IPropertyBag2 option list that the codec does not support, it is ignored.

Note for 16-bit and 32-bit Windows BMP files, the BMP codec ignores any alpha channel, as many legacy image files contain invalid data in this extra channel. Starting with Windows 8, 32-bit Windows BMP files written using the BITMAPV5HEADER with valid alpha channel content are read as WICPixelFormat32bppBGRA

[R C-R]

6 minutes ago, NotMyFault said:

this might be relevant an explain a possible root cause...

But why would it be an issue only in the V2 Affinity apps but not in the V1 apps, or for other apps like the Mac Preview app among others?

[NotMyFault]

21 minutes ago, R C-R said:

But why would it be an issue only in the V2 Affinity apps but not in the V1 apps, or for other apps like the Mac Preview app among others?

Affinity made some major refactoring under the hood to allow new functionality. They introduced new file formats. You may have noticed that several functions broke under V2 for the first time, or as regression. But ultimately, this is only guesswork. Only Affinity will be able to tell or find out.

[R C-R]

14 minutes ago, NotMyFault said:

But ultimately, this is only guesswork.

OK, but it still seems like a new bug introduced into the V2 apps, one that no other app (Affinity or otherwise) seems to have a problem with.

[thomaso]

7 hours ago, NotMyFault said:

use channels panel, select "Background Alpha", and "fill".

The solution reminds me to the issue afp-5540 (V1) – no idea if it's related to V2.

[NotMyFault]

5 hours ago, thomaso said:

The solution reminds me to the issue afp-5540 (V1) – no idea if it's related to V2.

Oh, i missed that. Channels Panel thumbnails for CMYK are shown inverted. Best visible if you create a spare channel. Still present in V2.

I think these are different causes with similar symptoms. CMYK is a subtractive model, whereas BMP files may have „garbage“ data in alpha channel which simply needs to be ignored when reading the file. 

[thomaso]

11 minutes ago, NotMyFault said:

Channels Panel thumbnails for CMYK are shown inverted.

I might be wrong but I guess the point was not just thumbnail appearance – but a black/white (fill/clear) confusion for some channels.

[NotMyFault]

3 minutes ago, thomaso said:

I might be wrong but I guess the point was not just thumbnail appearance – but a black/white (fill/clear) confusion for some channels.

That is correct. In V2.0.4 on iPad, the clear/fill confusion seems solved, but the thumbnail inversion is still unfixed.

[NathanC]

Thanks @NotMyFault for providing additional detail, I've confirmed this is a V2 regression that has been previously logged with the developers, i've now bumped the issue with this example file.

[NotMyFault]

Related bug report - looks like a déjà vu

[Affinity Info Bot]

The issue ".bmp file doesn't open correctly in V2 (it does in V1)" (REF: AF-5821) has been fixed by the developers in the latest beta build (2.6.2.3213). The fix is planned for inclusion in the next customer release.
Customer beta builds are announced here and you can participate by following these instructions.
If you still experience this problem once you are using that build version (or later) please reply to this thread including @Affinity Info Bot to notify us.